Hi Reddit! We discovered “Steve,” a mysterious purple light in the sky
related to auroras. We’re space and citizen scientists participating in
an initiative called Aurorasaurus and working with NASA. Ask us
anything!
Abstract
EDIT 4:35 pm ET: Thank you all for your excellent questions. It’s been a
lot of fun sharing our science with you. We’re signing off now. We have
just published a study detailing “Steve,” an aurora-related dancing
purple light first spotted – and named! – by amateur photographers.
This new information about Steve comes from analyzing satellite data,
all-sky cameras and additional citizen-scientist photographs. Steve’s
scientific name is now Strong Thermal Emission Velocity Enhancement
(which can still be shortened to STEVE). STEVE appears as a faint purple
ribbon of light in the sky and is often accompanied by a short-lived,
green, picket fence structure. It looks much like an aurora but occurs
at lower latitudes closer to the equator. After analyzing satellite
data, we learned that STEVE is the visible side of something we were
already familiar with: sub auroral ion drift (SAID), a fast moving
stream of extremely hot particles. SAIDs appear in areas closer to the
equator (like southern Canada) than where most auroras appear. Until
now, we never knew SAIDs had a visual component! Studying STEVE can help
us paint a better picture of how Earth’s magnetic fields function and
interact with charged particles in space. You can help us learn more
about STEVE by submitting your photographs and sightings of the
phenomenon to a citizen science project called Aurorasaurus (online at
aurorasaurus.org or on your device as iOS and Android apps). Check here
for more details about how to spot STEVE. Answering your questions today
are: Liz MacDonald, space scientist at NASA’s Goddard Space Flight
Center in Greenbelt, Maryland, and founder of Aurorasaurus Chris
Ratzlaff, citizen scientist who first named Steve; runs the Alberta
Aurora Chasers Facebook group Burcu Kosar, space scientist at NASA
Goddard Matt Heavner, space scientist at the New Mexico Consortium, Los
Alamos, New Mexico Bea Gallardo-Lacourt, space physicist at the
University of Calgary, Canada Bill Archer, space scientist at the
University of Saskatchewan, Saskatoon, Canada Megan Gillies, space
scientist at the University of Calgary, Canada We are now live. @NASASun
on Twitter